Trans-generational plasticity to warming reshapes nutrient recycling by a keystone grazer

Sarah Hasnain, Valerie McCarthy, Cihelio Alves Amorim, Lucia Cabrera-Lamanna, Emma Drohan, Zeynep Dilbe-Uyar, Gülce Yalçın, Dilvin Yıldız, Meryem Beklioğlu, Kemal Ali Ger

Human-driven environmental change can modify ecosystem processes by altering species traits and physiological responses. Stress-induced plasticity can modify organismal fitness and induce trans-generational responses impacting offspring fitness. However, whether trans-generational plasticity (TGP) impacts ecosystem functioning remains unknown. Here, we used reciprocal transplant experiments with the keystone freshwater grazer Daphnia magna to examine whether warming triggers TGP effects on grazing and nitrogen (N) and phosphorus (P) fluxes. Individuals were reared for two generations at either 18°C or 24°C. Offspring from the second generation were exposed to the same or reciprocal temperatures and we quantified algal clearance, and nutrient uptake and release. We did not observe any TGP effects on grazing rates. However, warmer maternal temperatures elevated offspring body P content and altered nutrient release, thereby increasing the dissolved N ratio. These results suggest that TGP can shift body stoichiometry and nutrient release under warming, with potentially important consequences for N and P cycling in lake ecosystems.